A. Garrigos

• Miguel Hernández University of Elche

The European Power Standard, used when designing and implementing spacecraft power buses, imposes stringent impedance requirements for high reliability and robustness, unlike other standards such as those from the American Institute for Aeronautics and Astronautics, SAE International, or the International Deep Space Interoperability Standard. These...

In [1], (A.7) and (A.8) are corrected as follows: \begin{align*} {{L}_m} &\approx 170\ \mu \mathrm{H}\\ {{C}_{TR}} &\approx 200\ \text{pF}\\ {{L}_{lk}} &\approx 650\ \text{nH}. \tag{A.7} \end{align*}

This paper presents the design of a digital twin for a 6U CubeSat electrical power system, including the solar arrays, solar array regulators, battery, power distribution unit, and load subsystems. The digital twin is validated by comparing its real-time outputs with those of the physical system. Experimental tests confirm its feasibility, showing...

This article proposes a photovoltaic power processor for high-voltage and high-power distribution bus, between 300 V and 900 V, to be used in future space platforms like large space stations or lunar bases. Solar arrays with voltages higher than 100 V are not available for space application, being necessary to apply power conversion techniques. The...

This work describes the implementation of three Maximum Peak Power Tracking methods devised for small satellites. The three methods are the Analog oscillating Maximum Power Point Tracking, the Analog Global Maximum Peak Power Tracking and the Analog Global Maximum Output Power Tracking. An interplanetary mission (Mars-Asteroid belt) with complex po...

This work presents a single point failure free solar array regulator design for scientific deep space exploration micro-satellites, where reliability and fault tolerance are critical design aspects. The proposed regulator is composed by six independent dc/dc Buck converters controlled by a double control loop, which can control both the battery end...

This paper proposes a solar array regulation technique for a high-voltage satellite power bus. The regulation method combines on-off control at low frequency, i.e. kHz range, of highly efficient isolated and unregulated dc-dc converters operating at high frequency, i.e. hundreds of kHz. Although this technique can adopt different implementations, t...

Power distribution using latching current limiters (LCLs) [also known as solid-state power controllers (SSPCs)] is very common for 28- and 50-V bus voltage distribution on European satellite platforms. However, 100-V and even higher voltage distribution platforms generally do not employ the same approach as lower bus voltage platforms since the com...

This article describes the design and implementation of a dc–dc converter used to power a microsatellite on-board electrolyzer. The proposed topology is a four-phase interleaved synchronous buck converter with output current control. The proposed converter is single point failure free (SPFF), so in case of any individual component failure, the func...

This paper details the design and implementation of a photovoltaic current – voltage (I-V) tracer. The I-V tracer employs a capacitive load controlled by a raspberry pi model 4B. The complete measurement system includes protections, capacitor charging/discharging power electronics and current, voltage, irradiance and temperature sensors. Results, w...

This work deals with the design of an electronic fuse for 380V dc distribution systems. It has been devised for applications that require current limitation up to 3A, so approximately 1.2kW. To protect the main semiconductor against excessive energy dissipation, the tripping time, defined as the time that circuit operates in current-limitation mode...

Many applications (electric vehicles, renewable energies, low-voltage DC grids) require simple, high-power density and low-current ripple-boost converters. Traditional step-up converters are limited when large transformation ratios are involved. In this work is proposed a step-up converter that brings together the characteristics of high gain, low...

This paper presents a new control strategy for reducing the switching losses produced by the use of high parasitic capacitance solar arrays in the sequential switching shunt regulator. Instead of dividing the solar array into equal sections, the proposed strategy is based on two different sections types, low-capacitance and high-capacitance ones. I...

This paper presents the possibility of using Gallium Nitride (GaN) high-electron-mobility transistors (HEMTs) instead of the conventional silicon metal oxide semiconductor field effect transistor (MOSFET) to implement a high-frequency intermediate bus converter (IBC) as part of a typical distributed power architecture used in a space power applicat...

This paper introduces a Solid State Circuit Breaker with Latching and Current Limiting capabilities for DC distribution systems. The proposed circuit uses very few electronic parts and it is fully analog. A SiC N-MOSFET driven by a photovoltaic driver and a maximum current detector circuit are the core elements of the system. This work details circ...

Nowadays, MOSFET SiC semiconductors short circuit capability is a key issue. SiC/Si Cascodes are compound semiconductors that, in some aspects, show a similar MOSFET behaviour. No interlayer dielectric insulation suggests, in theory, Cascode JFETs as more robust devices. The purpose of this paper is to compare the drift and degradation of two comme...

This paper presents a new ultrafast dc solid-state circuit breaker (SSCB) that uses a silicon carbide cascode as the main switching and limiting semiconductor and an isolated photovoltaic driver to control it. The proposed topology is self-powered and fully implemented with discrete parts. The SSCB's cascode can work in three different states—fully...

Energy conversion is one of the key steps for human utilizing the energy. In particular, as the key component for electromechanical energy conversion, electric machines play a significant role and greatly promote the development of modern civilization. Actually, the conventional types of electric machines, namely DC machines, induction machines, an...

Fuel cell power conditioners often require high step-up voltage gains to accommodate low input fuel cell voltages into high voltage busses. Traditional non-isolated DC-DC boost converters are unable to offer such as gains because of several parasitic elements and non-ideal behaviour of power semiconductors and driving circuits. Moreover, paralleled...

A bidirectional, interleaved, multiphase, multidevice, soft-switching, FPGA controlled, buck-boost converter with real-time PWM reconfiguration capabilities is presented and validated experimentally. This topology, named Multi-Interleaved Bidirectional Buck-Boost Converter (MIB3C), is intended for medium and high power bidirectional DC power condit...

In this paper a comparative analysis between different kinds of Silicon Carbide (SiC) transistors applied to the Sequential Switching Shunt Regulator (S3R) with active current limitation capability is presented. The S3R is a well-known Direct Energy Transfer photovoltaic power conditioner used in space vehicles. The main novelty discussed in this p...

This paper presents a System-on-Chip design for real-time satellites photovoltaic curves telemetry. In these applications, the limitation of memory and communication bandwidth makes quite difficult to store and to transmit the whole characteristic I-V curve of any solar section in real-time. The proposed solution is based on the real-time calculati...

In this work, an electronic system is presented to measure the force applied by a solenoid. The originality of the work is focused on the use of a magnetoresistive currentsensor to provide the isolation barrier needed in the actual industrial plant where the solenoids are working. The design of the electronic system is presented as well as experime...

This paper describes the simulation and implementation of a generic FPGA-based PWM generator with automatic device fault recovery. This PWM generator is applied to multi-switch DC/DC boost converters for fuel cell applications; these converters have gained attention due to its reliability, equally-distributed power losses and reduced part count. In...

The aim of this paper is to make an introduction, review and preliminary investigation tasks of the application of Silicon Carbide (SiC) power semiconductors and magnetoresistive (MR) current sensors for Solid State Power Controllers (SSPCs) and controlled switches, especially for high temperature environment and/or high voltage applications.

Non-isolated step-up voltage converters are commonly required as Battery Discharge Regulators (BDR’s). The Weinberg and boost derived topologies are traditionally employed in modules up to one or two kilowatts. The Interleaved Boost Converter (IBC) is a distributed power processing approach that provides some advantages: reduced power processing (c...

This paper presents the benefits and drawbacks of replacing the traditional Si Mosfets transistors with enhancement mode GaN transistors in a Half-Bridge Zero Voltage and Zero Current Switching Power Switching (ZVZCPS) converter. This type of converters is usually used as Electronic Power Converters (EPC) for telecommunication satellites travelling...

This work describes the practical implementation of an interleaved multi-phase, multi-switch boost converter for fuel cell applications. The paper aims to validate the concept of digitally-controlled Multi-Interleaving Boost Converter (MIBC) for fuel cell applications, from two-phase, four-legs per phase, synchronous boost converter, abbreviated as...

This work describes an interleaved multi-phase, multi-switch boost converter for fuel cell applications. Different options of PWM switching patterns are detailed with special emphasis in those that pursue input current ripple minimization and part reduction. The topology studied contains n power modules (phases) with m switches per module. From the...

The aim of this paper is to evaluate the benefits of replacing Si Mosfets transistors with enhancement mode GaN transistors in a Half-Bridge Zero Voltage and Zero Current Switching Power Switching Converter (ZVZCPS). This converter is usually used as power supply of the travelling-wave tube amplifiers (TWTAs) in aerospace applications. In this pape...

This paper covers the design and the implementation of the control strategy of a DC/DC converter aimed for hydrogen production from photovoltaic sources. This control scheme provides tight control of the injected current to the electrolyser and, if required, maximum power point tracking of the photovoltaic source, by means of two independent extern...

This work shows the design procedure followed to build the Power Converter Module (PCM) for the Polarimetric and Helioseismic Imager (PHI), experiment on board the Solar Orbiter Satellite (SolO). The selected topology has been a Push-Pull, for a power level of approximately 35 W and with seven output voltages. Coupled inductors between all outputs...

This paper describes the implementation of a hybrid energy storage system (HESS) using ultracapacitors (UCs) to protect the batteries of an electrical vehicle (EV) from high-peak currents and therefore extend their lifetime. A field-programmable gate array (FPGA) controlled interleaved bidirectional buck-boost converter working in a discontinuous c...

This paper presents a practical implementation of a photovoltaic I-V curves and maximum power point estimation algorithm (IVMPPE). The IVMPPE estimates the I-V curve and sets the operation of the solar panels at a voltage that extracts the maximum available power without tracking. The operation is based on solving the parameters of the solar array...

This paper describes an isolated, passive power factor correction rectifier devised for low-voltage, large-inductance, single-phase alternator, like the one used in the Radioisotope Stirling Generator. The power converter splits into two independent stages, the front-end rectifier corrects the power factor by adding a series capacitor in the AC lin...

Power converters for experiments that have to fly on board space missions (satellite, launchers, etc.) have very stringent requirements due to its use in a very harsh environment. The selection of a suitable topology is therefore not only based on standard requirements but additional more strict ones have also to be fulfilled. This work shows the d...

The Free-Piston Stirling Generator (FPSG) is a thermal to electrical energy conversion system, based upon the thermal engine of the same name. Intensive research concerning the feasibility of the engine for its application in deep space and planetary missions has been conducted, primarily due to the potential increase in efficiency (~30%) over the...

In this paper, a new real-time curve fitting method for photovoltaic (PV) modules is presented. The method solves the four-parameters photovoltaic cell model without scanning the entire I–V curve, without sensing irradiance or temperature and with no need of any manufacturer data. Only six pairs of voltage and current coordinates are needed to obta...

This work details a power conditioning unit for photovoltaic/hydrogen based energy systems in space applications. The power conversion techniques applied are similar to the ones used on photovoltaic/battery space power systems. A direct energy transfer photovoltaic regulator is devised for feeding two outputs; the first output corresponds to the ma...

A novel DC-DC power converter has been developed to fulfill the requirements of a solar electrical propulsion module. The maximum power point tracker solar array regulator is divided into two series converters; a direct-energy transfer (DET) regulator and a secondary step-up converter. The DET regulator creates an unregulated maximum power point bu...

The design and results of a high-efficiency high-power (5 kW) nonisolated bidirectional dc-dc converter is presented. High stability due to minimum phase behavior is an additional benefit of the topology. The converter is a new boost with output filter where input and output inductors are coupled. This converter is useful with any system that needs...

This work describes a step-up non-isolated DC/DC converter aimed for fuel cell stand-alone power systems. The proposed converter has the following features: simple structure based on the basic boost topology that reduces the number of components; it uses the interleaving technique in order to reduce the current ripple at the input and output sides,...

A new high-efficiency regulation method for a zero-current and zero-voltage current-fed push-pull converter is presented. The method proposed is based on the use of a controlled transformer as a post-regulator, which adds or subtracts an additional voltage to the output filter of the converter. An auxiliary regulator, which only handles a percentag...

This paper presents a new solution for a battery discharge regulator for high-power space applications (power-per-module ≥ 5 kW) using a high-efficiency step-up converter. Basic requirements are efficiency that is higher than 97%, mass that is lower than 2.5 kg, no galvanic isolation necessary, and a high mean time between failures. By taking into...

This paper describes a photovoltaic power regulator aimed for photovoltaic stand-alone hydrogen-backup power systems. The main characteristics of the regulator are the following; it employs a modular approach where each power cell has three ports, one input and two outputs, the input port is connected to a photovoltaic source while the two output p...

This paper covers the design of a DC–DC power converter aimed for hydrogen production from photovoltaic sources. Power conditioning for such application is usually driven by different constraints: high step-down conversion ratio is required if the input voltage of such equipment has to be compatible with photovoltaic sources that are connected to g...

An inner current loop is frequently used in many switching power supplies to achieve higher stability and a good current sharing. Nevertheless, some problems derived from its practical implementation can be encountered. One problem is related to the need of filtering of the sensed current and was discovered by the authors in the implementation of a...

Ion engines, also known as electrical propulsion, are used more and more in space applications due to its higher power density and its lower contamination risk than with chemical propulsion. One of its characteristics is that it needs a very stable power supply. This paper proposes a solution for the BepiColombo mission to Mercury. Electrical propu...

This paper presents the application of the parallel power processing strategy to the sequential switching shunt regulator for its use with high parasitic capacitance solar arrays. The main idea consists in dividing the complete solar array into two types of sections, low power sections and high power sections. The controller has been devised in suc...

In the following years power levels of 20 kW to 50 kW will be demanded by the telecommunication satellites. It is not possible to keep 0.5 kW modules with up to 100 modules in parallel and, therefore, higher power modules must be used. A higher bus voltage seems also necessary and any voltage below 150 V and above 100 V could meet the needs. In add...

Typically solar arrays are sized for EOL requirements and as a consequence some power is wasted at BOL. In addition, the number of payload channels (TWTA's) is also oversized for redundancy purposes. In a regulated bus, the surplus of power generated by the higher solar current at BOL can be used to supply more channels giving a benefit for extra s...

This paper describes a baseline solution of a Power Conditioning and Distribution Unit (PCDU) for Electrical Propulsion (EP) systems. The solution adopted uses two high efficiency, low-mass power regulators; a solar array regulator (SAR) based on the classical Sequential Switching Shunt Regulator with Maximum Power Point Tracking (MPPT) capability...

In this paper a solution for the power conditioning and distribution unit (PCDU) of the solar electric propulsion module (SEPM) is proposed. The electronic propulsion system is made out of ion thrusters which need a very steady supply voltage and therefore care has to be taken during switch off of the ion thrusters (beam-out) to avoid transient ove...

In this paper, an approximate curve fitting method for photovoltaic modules is presented. The operation is based on solving a simple solar cell electrical model by a microcontroller in real time. Only four voltage and current coordinates are needed to obtain the solar module parameters and set its operation at maximum power in any conditions of ill...

The purpose of this paper is describe a new conception of Power Conditioning Unit (PCU) developed to fulfill the requirements of BepiColombo Electronic Propulsion module. This load bus has very tough specification especially regarding transient response during total load switch-off ("beam out") which has to be less than 2% of the bus voltage. The c...

This work describes the principles of the sequential switching shunt regulator-digital shunt regulator, S3R-DSR, a novel approach to implement the solar array regulator. This is especially devoted to overcome the problems derived from the high solar array parasitic capacitance that exhibits the present (high power) telecommunications satellites

This work describes the principles of the sequential switching shunt series regulator, S4R, an innovative solution proposed by the European Space Agency and other partners to power the next generation of high power telecommunications satellites. A comparative study between, the S4R regulated bus vs. the traditional option, the sequential switching...

This work deals with the effect produced by the solar array capacitance on the sequential switching shunt regulator, S4R. In the past, silicon solar cells were widely used with practically no effect upon the solar array regulator, so that the solar array capacitance was a minor problem in the design. Nowadays, the usage of triple junction GaAs sola...

This paper presents the results of a project that looked after a high efficiency bidirectional converter which could be used as a battery discharge/charge regulator when the bus voltage is above the battery voltage. High efficiency, high stability and simplicity are the main goals, no galvanic isolation is required. Taking into account all these pa...

A novel maximum power point estimator (MPPE) for photovoltaic solar arrays is proposed, evaluated and implemented. Unlike maximum power point trackers (MPPT), the MPPE extracts the solar array maximum power with no tracking process. The operation is based on solving the solar array electronic equivalent model by a microcontroller in real time. Only...

The aim of this work is to obtain a dynamic model of the sequential switching shunt series regulator, S4R, valid for the different system domains and the operating working modes. Classical feedback control theory is applied after linearization of the power stage and design strategy is proposed. System simulations and experimental results are also p...

This paper presents the results of a high-efficiency high-power (5 kW) non-isolated bidirectional DC-DC converter. High efficiency, high stability and simplicity are the main goals, and no galvanic isolation is required. The proposed topology is a new BOOST converter with output filter where input and output inductors are coupled together which can...

The use of power MOSFET in regulated-dc electronic load is discussed. It uses two simple feedback loops to allow the transistors to work as a current drain in current-regulation mode or as a voltage source in voltage-regulation mode. Designers use current regulation mode when they are characterizing voltage sources, in which the power source must d...

A low-cost solar-array emulator formed from two bipolar transistors is described. An experimental setup is used to determine the electrical and physical characteristics of the whole system. The circuit implements an equivalent current source using two transistors and a diode, which actually forms a circuit with two topological states. Different mat...

The present paper shows the preliminary results of a project that looks for a high power, high efficiency bidirectional step-up converter which could be used as a battery discharge/charge regulator. High efficiency and low mass are the main goals, no galvanic isolation is required and MTBF should be as large as possible. Taking into account all the...

The present project was developed in order to find a high power (≥5 kW), high efficiency step-up converter which could be used as a battery discharge regulator. Efficiency should be higher than 97%, mass should be lower than 2.5 kg, no galvanic isolation was required and MTBF should be as large as possible. Taking into account all these parameters...

Firsts results on particle detection using a novel silicon pixel detector are presented. The sensor consists of an array of 48 square pixels with 380 μm pitch based on a n–i–p hydrogenated amorphous silicon (a-Si:H) film deposited on top of a VLSI chip. The deposition was performed by VHF-PECVD, which enables high rate deposition up to 2 nm/s. Dire...

Integrated particle sensors have been developed using thin-film on ASIC technology. For this purpose, hydrogenated amorphous silicon diodes, in various configurations, have been optimized for particle detection. These devices were first deposited on glass substrates to optimize the material properties and the dark current of very thick diodes (with...

We present the experimental results obtained with a novel monolithic silicon pixel detector which consists in depositing a n–i–p hydrogenated amorphous silicon (a-Si:H) diode straight above the readout ASIC (this technology is called Thin Film on ASIC, TFA). The characterization has been performed on 13 and 30 μm thick a-Si:H films deposited on top...

The sequential switching shunt series regulator-S4R, is a fully regulated bus and battery charger power cell devised for high power telecommunication spacecrafts. A mathematical characterization is obtained by means of the modeling of its power sources as nonlinear transconductances. Simulations and experimental measurements are presented to check...